Woolly Mammoths

Woolly Mammoths has trample as long as you control a snow land.

Earthlore

Enchant land you control
Tap enchanted land: Target blocking creature gets +1/+2 until end of turn. Activate only if enchanted land is untapped.

Tinder Wall

Defender (This creature can't attack.)
Sacrifice Tinder Wall: Add {R}{R}.
{R}, Sacrifice Tinder Wall: It deals 2 damage to target creature it's blocking.

Snow-Covered Island

Force Void

Counter target spell unless its controller pays {1}.
Draw a card at the beginning of the next turn's upkeep.

Counterspell

Wall of Pine Needles

Defender (This creature can't attack.)
{G}: Regenerate Wall of Pine Needles.

Lhurgoyf

Lhurgoyf's power is equal to the number of creature cards in all graveyards and its toughness is equal to that number plus 1.

Mystic Remora

Cumulative upkeep {1} (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)
Whenever an opponent casts a noncreature spell, you may draw a card unless that player pays {4}.

Infuse

Untap target artifact, creature, or land.
Draw a card at the beginning of the next turn's upkeep.

Scaled Wurm

Portent

Look at the top three cards of target player's library, then put them back in any order. You may have that player shuffle.
Draw a card at the beginning of the next turn's upkeep.

Clairvoyance

Look at target player's hand.
Draw a card at the beginning of the next turn's upkeep.

Snow-Covered Forest

Snow Devil

Enchant creature
Enchanted creature has flying.
Enchanted creature has first strike as long as it's blocking and you control a snow land.

Woolly Spider

Reach (This creature can block creatures with flying.)
Whenever Woolly Spider blocks a creature with flying, Woolly Spider gets +0/+2 until end of turn.